The Eartec Loop Inline PTT Headset for SC-1000 Radio Transceiver is a versatile headset for the SC-1000 simplex transceiver. It features Push-to-Talk activation. To use the Loop headset, simply plug it into the transceiver and clip the radio to your hip. Slip the rubberized ear loop over whichever ear you prefer. Finally, clip the lapel mic to your shirt collar or jacket. When you need to transmit, simply push the button on the lapel mic and speak; your voice will be transmitted immediately.